The correct answer is: [D]: " 
" .
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Explanation:
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;
Simplify the "denominator" ; → (b + 2b = 1b + 2b = 3b) ;
and rewrite:
;
Cancel out the "b" in the "numerator" to a "1" ;
and cancel the "3b" in the "denominator to a "3" ;
{since: "b ÷ b = 1 "; and since: "3b ÷ b = 3" } ;
and rewrite as:
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;
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→ which is: Answer choice: [D]: " " .
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Explanation:
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Simplify the "denominator" ; → (b + 2b = 1b + 2b = 3b) ;
and rewrite:
Cancel out the "b" in the "numerator" to a "1" ;
and cancel the "3b" in the "denominator to a "3" ;
{since: "b ÷ b = 1 "; and since: "3b ÷ b = 3" } ;
and rewrite as:
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→ which is: Answer choice: [D]: "
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